It has become something of a tired routine by now. North Korea conducts a nuclear test, China expresses disapproval, the US warns of dire consequences and the United Nations professes its dismay. Ultimately, precious little of consequence happens. The aftermath of the fifth—and largest—nuclear test carried out by the North Korean regime on Friday is unlikely to be any different.

The reasons are simple. Pyongyang’s value as a buffer against American influence in the Korean peninsula outweighs its annoyance value to Beijing. Consequently, with this latest test and the rash of missile tests in the recent past, Pyongyang is inching closer to delivery capability under the umbrella of Chinese forbearance.

The international non-proliferation regime is toothless as long as even a single major power chooses to play spoiler. Iran skated by for years for this reason; Israel continues to do so. Pyongyang is merely gaming this system.